Davit for lowering and raising ships&#39; boats.



AFP. LUNDIN & H. W. BROADY.

DAVIT FOR LOWBRING AND RAISING SHIPS BOATS.

APPLICATION FILED AUG. 1,1912.

Patented July 28, 1914 4 SHEETSSHEBT 1 A. P. LUNDIN & H. W. BROADY.DAVIT FOR LOWERING AND RAISING SHIPS BOATS APPLICATION FILED AUG.1, 19121,105,594. Patented July 28,014

A. P. LUNDIN & H. W. BROADY.

DAVIT FOR LOWERING AND RAISING SHIPS BOATS.

APPLICATION FILED AUG.1, 1912.

Patented July 28, 1 914.

4 SHEBTSSHEET 3.

wyd

UNITED STATES PATENT OFFICE.

ANDREAS LUNDIN AN D HARRY W. BROADY, OF BAYSIDE, NEW YORK; SAID BROADY 1ASSIGNOR TO SAID LUNDIN.

DAVIT FOR LOVVERING AND RAISING SHIPS BOATS.

Specification. of Letters Iatent.

Patented July 28, 1914.

Application tiled August 1, 1912. Serial No. 712,640.

I To all whom it may concern:

Be it known that we, ANDREAS P. LUNDIN and I'IARRY W. BROADY, citizensof the United States, and residents of Bayside,

county of Queens, and State of New York,

have invented certain new and useful Improvements in Davits for Loweringand Raising Ships Boats, of which the following is a specification.

Our invention relates to improvements in davits for ships boats andsimilar purposes. By the use of our invention we provide an extremelysimple, safe and inexpensive device for launching and swinging inboardships boats or other loads.

In the preferred embodiment of 'our 'invention we provide, incombination with a davit pivoted at its lower extremity, a link pivotedat one end to the davit intermediate the ends thereof and at its otherend pivoted to a traveling 'nut threaded on a screw supported in aninclined osition on the deck of the vessel so as to not longitudinalmovement and means for rotating the screw to compel the nut to travelalong the same, thus forcing the link and with it the davit arm to moveoutwardly or inwardly accordingto thedirection of rotation. Such aconstruction permits a longer power or actuating screw to be employed,saves valuable deck space and permits the more direct application ofpower. We furthermore referably so arrange the falls that the weig t ofthe boat will have a balancing effect and assist the operator in theactuation of the screw in that it relieves thrust on thescrew and pullson the link upwardly or outwardly until the davit arm ave rotary butreaches a point slightly beyond its perpen-,

dicular osition, from which point onward, the weig t of the boat willpull on the link and tend to retard the movement of the nut on thescrew.

In the accompanying drawings which illustrate a preferred embodiment ofour invention and in which similar reference characters designatecorresponding parts throughout the several views; Figure 1 is a sideelevation of a davit embodying our invention; Fig. 2 is an end elevationof the same; Fig. 3 is,a section on the line 3-3 of Fig. 1; Figs. 4 and5 are side and end elevations respectively of another modified form ofdavit operating mechanism embody- 55 ing our invention; Fig. 6 is adetail of the -not longitudinal movement.

ratchet and pawl mechanism shown in Figs.

4 and 5; and Figs. 7 and 8 are modifications upper end with suitablemeans for attaching the falls of a boat.

fB designates a triangular frame secured to the deck in any suitablemanner and C indicates a screw supported in an inclined position in saidframe to have rotary but Threaded on the screw C is a nut D providedwith trunnions 0 extending outwardly on each side thereof. A link E,bifurcated at its lower end is pivoted at that end on the trunnions cand its upper end is pivoted to the bracket a intermediate the ends ofthe davit arm A. Obviously when the screw is rotated, the nut will becompelled to travel along the same and the link E will push or pull thedavit arm outwardly or inwardly according to the direction of rotation.-

Suitable means for rotating the screw is provided. As illustrated inFigs. 1 and 2 we have shown a. worm wheel F fixed on the upper end ofthe screw C and aworm G supported in brackets g meshing with a wormwheel F and'rotated by a crank H.

It will beseen that by supporting the screw tively of the balancing orcompensating effect of the weight of the load, which in Figs. 1 and 2 isa boat- X, we preferably journal a pulley J on the bearing casing Bintermediate the ends of the screw and a suspension rope L runningthrough the suspension ul leys K and K is then led around the pn ley Jand has its other end connected to a cleat e on the lower end of thelink E.

As illustrated in Figs. 1 and 2, we provide two suspension blocks havinga plurality of pulleys running on parallel axes and consequently aplurality of parts of rope, though of course, a single pulley at the topof davit would answer the purpose. It will be seen that W1 .11 theweight of the boat rests upon the falls, the rope L will be drawn overthe pulley J and will pull upwardly on the link E and nut D and thispull will continue until the nut travels a sufficient distance along thescrew to move the davit to a substantially perpendicular position,whereupon the pull on said rope will be changed to a downward orretarding pull, thus assisting the screw in its negative or retainingaction as the weight of the davit exerts a pull on the link. Thisbalancing effect of the weight of the loadtherefore acts in twodirections during the swinging or oscillating of the davit in onedirection. Of course, in swinging the boat or load inboard, theoperation will be exactly thereverse of that above described.

In Figs. 4 to 8 inclusive we have shown a modified form of davitswinging mechanism embodying our balancing or compensating arrangementof the ropes and pillleys and said figures also show the application ofthe davit-swinging mechanism to two davits. In said figures, B indicatesa horizontally-disposed frame in which is mounted a screw C having a nutD threaded thereon. E designates a link pivotally connected at one endto the nut D and at the other end to the bracket (1 of the davit AL: Apulley J 2 is mounted on the frame B and the rope passes over the sameandis connected in a manner similar to that hereinabove described.

To actuate two davit/s simultaneously, we preferably extend the end ofthe screw C and fix thereon two ratchet wheels G which cooperate withtwo pawls h to permit the screw to be rotated in opposite directions,one. or both of the connected hand levers H being reciprocated for thispurpose. One pawl k is, of course, thrown out of engagement while theother is in engagement. In other respects the device is identical withthat shown inFigs. 1 and 2.

Having described our invention, we claim:

1. The combination with a davit arm pivoted at its lower end to swingfreely in a vertical plane to both sides of a perpendicular position, ofa frame secured to the deck of a vessel, a screw supported in said framein an inclined position to have rotary movement only, a nut threaded onthe screw, a link connecting said nut and davit arm and means forrotating the screw.

2. The combination with a davit arm pivoted at its lower end to swingfreely in a vertical plane to both sides of a perpendicular position, ofa frame secured to the deck of a vessel, a screw supported in said frameto have rotary movement only, a nut threaded on the screw, a linkconnecting a point on the davit arm intermediate its ends with the saidnut, and a flexible connection between the load and a moving part of themechanism for exerting a balancing pull on the davit in two directionsduring the movement of said davit in one direction.

3. The combination with a davit arm ivoted at its lower end to swingfreely in a vertical plane to both sides of a perpendicular positlon, ofa frame secured to the deck of a vessel, a screw supported in said frameto have rotary movement only, a nut threaded on the screw, a linkconnecting a point on the davit arm intermediate its ends with the saidnut, apulley mounted on said frame intermediate the ends of said screwANDREAS P. LUNDIN. HARRY W. BROADY.

Witnesses:

FREDERICK P. RANDOLPH, HELEN V. HOLMES.

